The present invention relates to an apparatus for milling or flouring granular material such as wheat or the like, and to a system comprising a plurality of milling apparatus each of which includes a roll mill.
In milling operation by which granular material to be milled such as wheat or the like is milled to flour, the granular material is supplied to a roll mill where the granular material is milled. However, the granular material is not milled to powder at a time. Specifically, a plurality of roll mills are arranged in series, and are functionally combined with a plurality of sorting units and a plurality of transporting units to obtain milled material of the wheat or the like such as flour, that is, to obtain a product which is milled to a requisite particulate or milling degree.
Special attention is required to be paid to adjustment of the milling degree of the milled material at each of the roll mills, arrangement of screens or sieves of each of the sorting units such as sieve sorters, and so on, in order to efficiently operate the plurality of roll mills and sorting units to produce the milled material of high quality. In each of the roll mills, a spacing or a gap between a pair of rolls is particularly a primary factor which affects the milling degree. Considerable time is required for adjustment of the gap. Further, differences in various characters such as a particulate or grain size of the granular material to be supplied, moisture content of the granular material, and so on, are revealed as a difference in the milling degree. Even in the course of the operation, the milling degree changes so that inspection and adjustment of the gap between the pair of rolls are required.
Moreover, there is a measuring device for judging the milling degree, in which, after sieve sorting, the milling degree is judged on the basis of comparison in weight of the sorted milled particles. However, because of sorting of the powder, the necessity remains in which attention is paid to selection of the sieves, their arrangement and so on.